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Apache Wicket needed to improve the implementation of its JavaScript libraries used for Ajax functionality (wicket-ajax.js and wicket-event.js) by using any of the bigger JavaScript libraries and delegate to it the handling of the differences in the browsers (DOM, events, Ajax, ...). After a discussion in the mailing lists the Wicket team decided to use JQuery for that.
For more information read https://cwiki.apache.org/confluence/x/NK2oAQ Wicket Ajax
package.properties renamed to wicket-package.properties
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